contact us Get in touch with a Consultant

October 29th, 2009:
Article: Retrofit of Sydney Building Includes Cogeneration Plant

Cogent Energy has designed and installed a cogeneration plant at a 40,000m2 office building in Sydney. The company also designed the electrical and mechanical interfaces between the cogeneration plant and the building’s distribution systems. The building owner is Mirvac.

The plant has two 1166kW cogeneration engines from MTU’s 4000 series that are connected in parallel to the grid. Each engine is coupled to a 750kW Thermax exhaust absorption chiller. The chillers are integrated into the building’s chilled and condenser water systems. The plant is set up to operate in grid parallel import and island mode and operates automatically during the peak and shoulder demand periods.

The project was a retrofi t of an existing building which was undergoing major refurbishment to upgrade its environmental credentials according to the NABERS rating. The plant had to be fitted in to an existing plant room in the basement of the building. The engineers demonstrated creative thinking to successfully fi t all the equipment into the plant room next to existing infrastructure. “For example, there is a major storm water pipe going through the basement and our equipment had to be positioned to fi t around this,” said the company’s general manager for NSW Nalin Wickramasinghe.

Access to the basement was also difficult as the crew had to cut through concrete and plan a major traffi c control exercise to move the plant in. The four major pieces of equipment –two engines and two absorption chillers – weighed close to 50t which presented a logistical challenge in moving them to a commercial location in Sydney. The building’s electrical switchboards which date back to 1990 also had to be significantly upgraded to match the cogeneration plant’s system. The metering for the entire building had to be revamped signifi cantly to ensure that the tenancies are invoiced correctly.

The commercial structure of the project involves the company using energy supply agreements to sell metered electrical and thermal energy to the building owner and the tenants. The company will own, operateand maintain the plant over a twelve-year contract period.